1. Field of the Invention
This invention relates to new vanadium (IV) alcoholates which are soluble in organic solvents and have greater stability than known vanadium alcoholates.
2. Discussion of Prior Art
Alcoholates of tetravalent vanadium, which are used, for examples, as polymerization catalysts, are already known. They correspond to the formula V(OR).sub.4 and they are soluble in some polar organic solvents. However, they are expensive and difficult to prepare, because they cannot be made by the direct reaction of VCl.sub.4 with alcohols, because of the proneness of this compound to hydrolysis. Instead, VCl.sub.4 has to be reacted with lithium dialkylamide and the tetrakis-(dialkylamino) vanadium (IV) thus obtained must be subjected to alcoholysis.
These known alcoholates of tetravalent vanadium also have the disadvantage that they are not thermostable. At temperatures above 100.degree. C., they begin to decompose. Their shelf life also leaves much to be desired, and they can be stored satisfactorily only if certain precautionary rules are followed. Also the alcoholates of pentavalent vanadium, such as for example VO(OCH.sub.3).sub.3 or VO(OC.sub.2 H.sub.5).sub.3, which are also used as catalysts, have the same instability, so that they are not satisfactory replacements for the vanadium (IV) compounds.